Postpartum Hormones

In most cases pregnancy is a very special time that couples, and especially women, look forward to. Ideals, expectations and desires are all focused on the period up until the point of childbirth or up until the day on which the baby is born. In the majority of cases people tend to overlook the period immediately after childbirth, the puerperium, which can be a very unique and tricky time.  

The postpartum period, also known as the puerperium, or the “fourth trimester,” refers to the period immediately after childbirth when any physiological changes in the mother’s body in relation to the pregnancy are reversed and her body returns to the pre-pregnant state. In addition to the physiological changes and problems that can occur during this period, healthcare professionals also need to be aware of the mother’s psychological needs during postpartum and be sensitive to cultural differences surrounding childbirth.¹

It is generally agreed that the postpartum period starts at the point of childbirth. When it ends is less clear, but the consensus is that it ends six to eight weeks following delivery as the effects of the pregnancy gradually begin to be reversed and the mother’s body returns to the pre-pregnant state. However, as the mother’s body returns to this state, it does so gradually and often in waves. According to the American College of Obstetricians and Gynecologists, postpartum care should be provided for up to 12 weeks following delivery.²

Human chorionic gonadotropin (hCG) is the primary hormone produced during pregnancy, but levels drop immediately after delivery and the disappearance of hCG postpartum follows a biexponential curve.³  The hormone persists for some time after this drop with hCG values usually returning to normal non-pregnant levels two to four weeks after full-term delivery, although this may take longer.⁴

Some women report hot flashes during the postpartum period which improve over several weeks.⁵  The cause is unclear but it may be due to thermoregulatory dysfunction initiating in the hypothalamus from the decline in estrogen following delivery resulting from placental expulsion. In addition, the initial hyperprolactinemia associated with breastfeeding reduces estrogen production and contributes to these hot flashes.  

Gonadotropin and sex hormone levels are low during the first two to three weeks following delivery. In studies that used urinary pregnanediol levels to measure ovulation in nonlactating women, the meantime for the return of menses following delivery ranged from 45 to 64 days and the mean day of first ovulation ranged from 45 to 94 days but could occur as early as 25 days after delivery.⁶  Breastfeeding suppresses the secretion of gonadotropin-releasing hormone (GnRH) such that it is modulated by the frequency of breastfeeding and by the maternal nutritional status and body mass,⁷  given that lactation represents a metabolic energy load. Approximately 40% of women will remain amenorrhoeic for six months following delivery during exclusive breastfeeding.⁸  Amenorrhea during breastfeeding may be related in part to higher prolactin levels than in women who are ovulating during breastfeeding since prolactin inhibits the pulsatile release of GnRH from the hypothalamus. In a study some exclusively breastfeeding women (minimum of six nursing episodes a day totaling more than 80 minutes over 24 hours) had hyperprolactinemia and amenorrhea for a year or more following delivery.⁹

Breast engorgement results from inflammation of the breasts and is accompanied by pain and sensitivity. The affected area can vary, from the areola to more peripheral regions. This is primarily due to the interstitial edema and the start of the abundant production of milk. It generally occurs 24 to 72 hours after delivery and ranges typically from one to seven days. Symptoms peak on average three to five days after delivery. However, it can also occur later if the mother’s milk supply exceeds the amount of milk consumed by the baby. Breast engorgement is uncomfortable and may cause a slight temperature increase for a short period, however, any fever should be investigated to rule out a source of infection. The condition spontaneously resolves itself after a few days. Still, supportive care can be used such as warm compresses or a hot bath before breastfeeding which can speed up the reduction in size and facilitate the removal of milk, cold compresses after or between breastfeeding sessions, massaging of the breasts and analgesic painkillers.  

Chloasma on the skin shows signs of improvement, however, it is unknown when this occurs.  

The increase in the proportion of hair growing (anagen phase) in relation to hair resting (telogen phase) during pregnancy is reversed during puerperium. Telogen effluvium is hair loss commonly seen from one to five months after delivery. It is generally self-limited and normal hair patterns are restored 6 to 15 months after delivery.  

The reduction in uterine volume associated with lochia and excessive intracellular and extracellular fluid leads to a loss of 2 to 7 kg during puerperium.¹⁰  Approximately half of the gestational weight gain is lost during the first six weeks after delivery followed by a slower loss rate during the first six months.¹¹

Physiological changes in the cardiovascular system occur in the first 10 minutes following full-term vaginal delivery and the cardiac output and stroke volume increase by approximately 60% and 70%. One hour after delivery, both the cardiac output and the stroke volume remain increased (by about 50% and 70%), whereas the heart rate decreases by 15% and blood pressure remains unchanged. Increases in the stroke volume and cardiac output are probably the results of the improvement in the cardiac preload from the autotransfusion of uterine-placental blood to the intravascular space. As the uterus decompresses following delivery, a reduction in the mechanical compression of the vena cava enables additional increases in the cardiac preload. A study assessing the cardiac output and stroke volume in 15 healthy patients without labor at 38 weeks of pregnancy and again 2, 6, 12 and 24 weeks after delivery showed a gradual reduction in cardiac output from 7.42 L/min at 38 weeks of pregnancy to 4.96 L/min at 24 weeks after delivery.¹²    

Hematological changes related to pregnancy return to baseline values within 6 to 12 weeks after delivery. It is important to point out that the prothrombotic state takes weeks to resolve itself so women in postpartum have an increased risk of suffering thromboembolic disorders.  

Although childbirth is typically a joyous event many women develop depressive symptoms and disorders in the postpartum period.¹³  Patients may display postpartum depression consisting of mild symptoms of depression which are generally self-limited or more severe syndromes of major or minor depressive disorder. If left untreated postpartum depression can have adverse consequences for the mother and the baby.  

The pathogenesis of postpartum depression is unknown. It is also unclear how much the basics of postpartum depression differ from those of non-perinatal depression¹⁴  and whether postpartum depression represents a distinct subtype of depression. Factors involved in postpartum depression may include genetic susceptibility, epigenetic phenomena like DNA methylation, hormonal changes, psychological and social problems, and stressful life events.¹⁵

Changes in serum concentrations of various hormones are associated with postpartum depression including reductions in estrogen and progesterone. Other changes involve cortisol, melatonin, oxytocin and thyroid hormone. Although hormone levels usually fluctuate during pregnancy and after delivery, increasing sensitivity to these normal changes may predispose women to depression.¹⁶  For example, differences in the activity of specific genes in the hippocampus may increase susceptibility to postpartum depression making women more sensitive to the decline in estrogen that occurs following childbirth.¹⁷  

Evidence supporting the hypothesis that endocrine factors are involved in the pathogenesis of postpartum depression includes a study designed to simulate the hormonal changes that occur during delivery. The study compared eight women with a history of postpartum depression with eight women without a significant history of depression.¹⁸  All of the individuals were treated with supraphysiologic doses of estradiol and progesterone which were then withdrawn over four weeks. The increase in depressive symptoms during the withdrawal period occurred in five of the eight women with a history of postpartum depression but none of the women without a history of depression suggesting that women with a history of postpartum depression may be exceptionally sensitive to sudden decreases in gonadal hormones.

The placenta is a fetal endocrine organ and the disruption of placental corticotropin-releasing hormone may play a role in developing postpartum depression. A study (n = 100 pregnant women) showed that elevated levels of the placental corticotropin-releasing hormone at 25 weeks gestational age were a strong predictor of postpartum depression at a mean of nine weeks after delivery.¹⁹  A subsequent study with n = 170 pregnant women discovered that elevated midgestational placental corticotropin-releasing hormone was associated with depressive symptoms three months after delivery.²⁰  

Changes in the neurotransmitters may also be involved in the pathogenesis of postpartum depression. A study of postpartum women discovered that the density of the enzyme monoamine oxidase-A in the prefrontal and anterior cingulate cortex was elevated amongst women with postpartum depression compared to the control group.²¹  The enzyme which metabolizes neurotransmitters such as dopamine, norepinephrine and serotonin, alongside the swifter depletion of such neurotransmitters, may lead to depression. Other studies suggest that serotonergic activity is reduced during postpartum depression.²²  

A prospective study measured the brain-derived neurotrophic factor in postpartum women (n = 340) one to two days after delivery and discovered that the serum concentrations were lower in women (n = 37) who subsequently screened positive for depression three months after delivery.²³  

Symptoms of postpartum unipolar major depressive disorder and of major depressive episodes that occur outside the postpartum period appear to be similar. By way of example, a nationally representative study conducted in the United States included women with postpartum major depressive disorder (n = 81) as well as women with non-postpartum major depressive disorder (n> 1,300). Within each group the study examined the prevalence of each of the nine depressive symptoms used to diagnose the unipolar major depressive disorder and found little difference between the two groups.²⁴    

Untreated postpartum depression may resolve itself spontaneously or with treatment or develop into a (chronic) persistent depressive disorder. A review of clinical and community samples of treated and untreated patients concluded that postpartum major depressive episodes last at least one year in 30% - 50% of patients. This appears to be roughly comparable with that observed for major depressive episodes outside puerperium.²⁵    

Postpartum depression has a negative effect on the mother’s routine, is associated with poor nutrition and health of the offspring and may interfere with breastfeeding, the mother-child bond, the baby’s care, and the mother’s relationship with her partner. Furthermore, postpartum depression is associated with children's abnormal development, cognitive deficit and psychopathology.²⁶

Postpartum depression may involve thoughts of infanticide. Such thoughts may be described as “scary thoughts” and are generally not revealed unless patients are directly asked. Thoughts of infanticide are generally considered to be unacceptable and intrusive. However, such thoughts may indicate that patients are psychotic and therefore require an assessment of psychotic symptoms, such as delusions or hallucinations.²⁷  

It is essential to carry out an early diagnosis with the support and supervision of an experienced obstetrician to ensure that the best approach is adopted based on the extent of psychological changes.  

Cognitive-behavioral therapy (CBT) combines cognitive therapy with behavioral therapy. Cognitive therapy aims to change dysfunctional thoughts and beliefs concerning illness; behavioral therapy aims to change problematic behaviors that occur in response to dysfunctional thoughts, depressive symptoms and environmental stimuli.  

Interpersonal psychotherapy focuses on improving problematic interpersonal relationships or circumstances directly related to the current depressive episode. Such interpersonal problems include disputes over roles like marital conflicts and changes in roles like becoming a mother.  

Behavioral activation is a component of CBT generally administered by patients themselves. The intervention aims to neutralize lethargy and avoidance by encouraging rewarding activities and behaviors, reducing avoidance behaviors and rumination and helping patients improve their problem-solving skills.  

Non-directive counseling (also referred to as a listening session) aims to help patients understand and accept their feelings, values, and behavior. The rhythm, direction and content are determined by patients; the therapist acts as a facilitator, encouraging patients to talk instead of providing explanations or interpretations. Nurses tend to administer non-directive counseling at patients’ homes, while other forms of psychotherapy are typically offered at clinics by therapists who hold a Ph.D.  

Psychodynamic psychotherapy aims to improve understanding of repetitive conflicts by identifying patterns of relationships, feelings and behaviors; patients work on developing more productive coping strategies (defense mechanisms).