How hormones change after giving birth

What happens straight after birth

The most dramatic hormonal changes happen in the first 1 to 2 weeks after giving birth. The body shifts from pregnancy mode to recovery and lactation mode very quickly.

Oestrogen and progesterone crash

During pregnancy oestrogen and progesterone reach levels far above anything in a normal menstrual cycle. The placenta produces enormous amounts. When the placenta is delivered after birth those hormones fall off a cliff. Within 24 to 48 hours oestrogen and progesterone drop to very low levels. This single change probably contributes to many of the physical and emotional symptoms of the first postpartum week.

Prolactin rises

Prolactin is the hormone that drives milk production. It rises through pregnancy and surges further after birth, particularly with breastfeeding. High prolactin maintains lactation. It also suppresses ovulation, which is why many breastfeeding women do not have periods for several months. This is called lactational amenorrhoea and is one of the body's built in spacing mechanisms.

Oxytocin during breastfeeding

Oxytocin is released during breastfeeding and supports milk let down, uterine contraction back to its pre pregnancy size and emotional bonding. It is one of the genuinely positive hormonal patterns of the postpartum period. Skin to skin contact and breastfeeding both promote oxytocin release. This is partly why these activities feel calming for many mothers.

The baby blues

Around 70 percent of women experience the baby blues in the first 1 to 2 weeks after birth. Tearfulness, mood swings, emotional sensitivity and overwhelm are common. This is the hormonal crash playing out. The baby blues are different from postnatal depression. They typically settle within 2 weeks. If symptoms persist or worsen beyond this, speak to your GP or health visitor.

The lactation hormonal pattern

Breastfeeding produces a specific hormonal pattern that differs significantly from non breastfeeding postpartum recovery. The pattern affects everything from cycles to mood to body composition.

Suppressed reproductive hormones

Continuous breastfeeding suppresses oestrogen and progesterone production. The body holds these hormones low to prioritise milk production. The result is a hormonal state more similar to early menopause than to the typical reproductive years. Some women experience symptoms that overlap with menopause including hot flushes, mood changes, joint aches and reduced libido.

Lactational amenorrhoea

Many breastfeeding women do not have periods until they start reducing feeds. The length of amenorrhoea varies hugely. Some women have periods return within 3 months even while exclusively breastfeeding. Others have no periods for 12 to 18 months or longer. The pattern depends on how often and intensely the baby feeds.

The dryness issue

Low oestrogen during breastfeeding causes vaginal dryness for many women. This can make sex uncomfortable and may produce other symptoms similar to menopausal vaginal atrophy. The effect is reversible. Vaginal moisturisers and lubricants help in the meantime. The dryness improves significantly as oestrogen returns when breastfeeding reduces or ends.

Returning to cycles

When you reduce breastfeeding the suppression of reproductive hormones eases. Ovulation usually returns before the first period. This means you can get pregnant again before you have had any period. If you are not planning to conceive again immediately, this matters. Contraception can be needed sooner than people expect after birth.

Months 3 to 12 and beyond

The hormonal recovery from pregnancy and birth continues for many months after the immediate postpartum period. Some changes resolve in weeks. Others take much longer.

Thyroid function

Around 5 to 10 percent of women develop postpartum thyroiditis in the first year after birth. The thyroid first becomes temporarily overactive, then often underactive, then often recovers. Symptoms can mimic typical postpartum tiredness or depression. Thyroid testing is worth raising with your GP if you have persistent symptoms in the first year after birth.

Mood and mental health

Postnatal depression affects 10 to 15 percent of women and can develop any time in the first year. Anxiety is increasingly recognised as common postpartum. Hormonal factors contribute alongside sleep deprivation, the demands of new parenthood and individual vulnerability. Effective treatment is available. Speaking to your GP, health visitor or midwife is the first step if you are struggling.

Body composition and weight

Some women lose pregnancy weight quickly. Many do not. The body remains in a slightly different metabolic state for months. Breastfeeding burns calories but does not produce reliable weight loss for everyone. Aggressive dieting while breastfeeding can affect milk supply and is not recommended. The body needs time. Patience and gradual changes work better than fast fixes.

Hair, skin and other physical changes

Postpartum hair shedding around 3 to 6 months after birth is normal and reflects the loss of pregnancy hair retention. It can be alarming but is temporary. Skin changes including melasma and changes in pigmentation may take many months to settle. Joint laxity from pregnancy resolves over several months. Some changes are permanent. The body does not return exactly to its pre pregnancy state.

What to know about the postpartum hormonal experience

Postpartum hormonal changes are real, intense and often poorly explained. Some practical points help women navigate this period.

It is not just sleep deprivation

Postpartum symptoms get attributed to lack of sleep, which is real. The hormonal changes are also significant. Acknowledging that some of what you feel has a biological basis can be helpful. The crashing hormones combined with sleep deprivation combined with caring for a new baby is genuinely a lot. The fact that women have been doing this throughout human history does not make it easy.

When to ask for help

Persistent low mood, anxiety that affects function, thoughts of harming yourself or the baby, ongoing tearfulness beyond 2 weeks or feeling unable to cope all warrant speaking to your health visitor or GP. Postnatal mental health support has improved significantly in recent years. There is no medal for struggling on your own. Help is available and effective.

Contraception choices

Ovulation can return before periods, which means pregnancy before periods is possible. Contraception needs to be considered before sexual activity resumes if you want to space pregnancies. The pill is generally not recommended during breastfeeding. The progesterone only pill, implant, injection and IUDs are options. Your GP or midwife can discuss what suits you.

The long view

Hormonal recovery from pregnancy and breastfeeding takes 6 to 12 months for most women, longer for some. Cycles may be different than they were before. Some women find their PMS or cycles change permanently. The postpartum period also affects long term health in various ways. Most of these effects resolve. Some persist. The body is changed by the experience.

More on female health

For the pregnancy context our What to Eat During Pregnancy covers nutrition during the antenatal period. How Depression Affects Women at Different Life Stages covers postnatal depression in context. And The Key Hormones That Drive Female Health covers the hormonal background.