The synthesis of corticotropin-releasing hormone by the placenta causes cortisol levels to peak in late pregnancy and then sharply decline at delivery. Urinary-free cortisol, also known as plasma cortisol, has not been related to PPD in several studies (Borgsted et al., 2022). A study that found a beneficial association across early levels of serum cortisol, measured 6 weeks after giving birth, and the level of dysphoria in women was complicated by the fact that breastfeeding timing and the inability to control stressful life events can cause cortisol levels to rise or fall, respectively (Baattaiah et al., 2023).

Following childbirth, there is a modest increase in the prevalence of impaired thyroid function. Thyroid dysfunction affects women in the 6 months after giving birth, compared to the general population. Thyroid dysfunction could contribute to PPD in a subset of women, even if it has not been found in the majority of these women (Cheng et al., 2022). Seven percent of the 303 pregnant euthyroid women in the prospective trial went on to develop postpartum thyroid problems. Treatment for thyroid dysfunction addressed the depression that was found in 38% of these mothers. Weight gain, cold sensitivity, and tiredness are indications of hypothyroidism; thus, measuring thyroid function is a crucial component of assessing PPD in women with these symptoms (Luo et al., 2023).

In late pregnancy, prolactin levels increase from pregravid levels and in nonlactating women, they decrease in the 3 weeks following birth. Prolactin levels in mothers rise for a few months before falling to levels seen before pregnancy (Barooj-Kiakalaee et al., 2022). There has been no research done on the relationship between PPD and the posterior pituitary chemicals oxytocin and vasopressin, which change in amounts throughout the postpartum phase. During labor, oxytocin stimulates uterine muscle contraction and encourages the flow of breast milk (Yadav et al., 2023). It also rises dramatically during delivery and throughout breastfeeding. A measure of mood state, vasopressin, which controls blood pressure and electrolyte balance, was shown to be lower in postpartum women’s urine but not in their plasma when compared to nonpuerperal women (Avila-García and Figueroa-Damián, 2023).

The physiologically active forms of estrogen, estradiol, and estriol are produced by the placenta and increase by times throughout pregnancy. Estriol is produced in large quantities during pregnancy because it is a byproduct of the fetal liver’s metabolic activities (Barinov et al., 2022). Estradiol has been shown in animal experiments to improve neurotransmitter function by increasing serotonin production and decreasing its breakdown (Kim et al., 2022). Therefore, PPD could be exacerbated by the sudden drop in estradiol levels after delivery (Al Beloushi et al., 2024). The degree of alteration in total oestradiol or complimentary oestriol since delayed pregnancy, however, did not differ significantly between depressed and no depressed women, according to a maximum pregnant lady (Yilma et al., 2023).

For instance, compared to other women, pregnant women had a 70% lower risk of developing rheumatoid arthritis symptoms (Gottschling et al., 2024). However, there is a significantly higher chance of getting it during the postpartum phase, especially in the first three months. The relapse rate in women with multiple sclerosis falls during pregnancy, rises during the first three months of the postpartum phase, and then falls back to the pre-pregnancy rate (Shmakov et al., 2022).

Other autoimmune conditions, such as Hashimoto thyroiditis and Graves’s disease, also resolve on their own during pregnancy before getting worse after giving birth (Vasconcelos et al., 2022). Three to six months after giving birth, 70% of moms with positive thyroid stimulating antibody screening test findings experienced either temporary or permanent postpartum Graves’s disease. Additionally, postpartum cases of autoimmune myocarditis, idiopathic polymyositis, hemolytic uremic syndrome, antiphospholipid antibody syndrome, and sarcoidosis have been reported (Zaigham et al., 2022).

Women throughout their postpartum period were afflicted with a variety of infections, including bacterial, fungal, and viral infections (Tesfaye et al., 2022).

Immunological tolerance at the matemal-fetal interface depends on endocrine-driven mechanisms and the interaction of lymphocytes and antigen-presenting cells (APCs). Cytokine-producing CD56brightCD16- uNK leukocytes, which are the most common (50%–70%) during the first trimester of pregnancy, help with embryo implantation and trophoblast invasion and differentiation (Kazemi et al., 2023). Among other aspects, uNK cell formation, proliferation, and the synthesis of chemicals that promote embryonic growth are influenced by the activation of the estrogen receptor β and HLAG/ILT2.

HLA-G/ILT2-ILT4 signaling in the uterus stimulates the development of M2 macrophages with scavenger receptors and anti-inflammatory characteristics. By producing IL-10, the regulatory responses were removed. Subpopulations of lymphocytes mediate immunological tolerance toward fetal alloantigens and coordinate cellular responses against exogenous antigens (Kuravska et al., 2022). Table 5 represents the immune and hormone responses during pregnancy.

It has been proposed that one of the factors causing PPD in certain women is the significant drop in maternal progesterone and estrogen levels that occurs after delivery. Estrogen not only enhances neurotransmitter function but also changes the hypophyseal-pituitary axis, reduces oxidative stress, and encourages neuronal growth and survival (Naghshineh et al., 2023). In an effort to replicate the hormonal shifts that take place around the time of delivery, this was done. Initial results from using estrogen to treat PPD have been favorable (Ye et al., 2023).

The significance of early and precise identification and therapy for depressive disorders during or throughout pregnancy has come into greater focus in an effort to lessen the severe negative impacts of PPD.

Diagnoses of PPD could be more difficult because of the typical substantial and expressive difficulty of the new maternity period, such as altered energy and appetite, lack of sleep, and heightened anxiety over the baby (Dessì et al., 2024).

The potential impact of depressive drugs on nursing worries a lot of women and professionals. Neonates and early newboms are especially vulnerable to the negative effects of some medications due to their growing neural systems, underdeveloped hepatic and renal systems, and undeveloped blood-brain barriers. Several specialists have suggested nonpharmacologic therapy methods wherever possible, especially for mild to moderate depression, due to the paucity of information regarding the effects of antidepressant medication in breast milk (Jyotsna et al., 2023).

PPD could be a subtype of major depression that reacts similarly to antidepressant drugs, according to a modest but increasing body of research. The pharmacological action of PPD increases anxieties about postnatal metabolic variations, the infant’s contact to medication in breast milk, the influence of unhappiness and handling on the miserable mother’s capacity to care for a newborn, and the dishonor related with being branded a bad mother for demanding medicine (Rupanagunta et al., 2023).

Many mothers with PPD are reluctant to use antidepressants and often choose for psychological therapy instead, due to worries about potential side effects or about exposing their infant to medicine through breast milk. The evidence that is currently available supports the use of emotional therapies, even if research on nonpharmacologic treatments for PPD is yet in its early phases (Kleiman, 2022). Both psychological and psychosocial therapy are effective in reducing depression and are a significant alternative for treating PPD, according to a study often randomized controlled trials. These therapies include non-directive counselling, cognitive behavioral therapy, interpersonal therapy, and support from partners and peers (Gunduz-Bruce et al., 2022).

Omega-3 fatty acids have gathered special kindness in the treatment of perinatal unhappiness due to their well-established wellbeing compensations for anxious and postpartum women, as well as some indication of their positive belongings on mood in the general people. The development of a fetus’s central nervous system depends on omega-3 fatty acids present in fish oils. This process is aided by the mother’s omega-3 fatty acid depletion during pregnancy (Xie et al., 2024).

The principle of the examination is to investigate the hormonal-immune interactions that take place throughout pregnancy and their effects on maternal health, particularly postpartum recovery. Overall, healthy pregnancy and the development of the fetus depend on the hormonal-immune interactions that control the mother’s immunological tolerance during pregnancy. PPD is largely caused by hormonal changes that occur after delivery, especially the decrease in progesterone and estrogen, which calls for cautious control. Nonpharmacological therapies like psychological support, breastfeeding assistance, and nutritional interventions like omega-3 fatty acids are just as important for promoting maternal recovery as hormone therapy and pharmaceutical treatments, which offer promising avenues for alleviating postpartum mood disorders. To address the various requirements of mothers during the postpartum period and to guarantee their general wellbeing, a thorough and customized approach that combines medical and psychological assistance is necessary. To prevent and cure PPD, future studies should concentrate on investigating individualized hormonal and immune-based treatments. The long-term impacts of combining pharmaceutical and non-pharmacological interventions on maternal health also require more research.