It is possible to conceive while breastfeeding, even before your menstrual period returns. This often surprises new parents. Understanding postpartum fertility is important for those seeking to prevent or plan another pregnancy.
Hormonal Impact of Breastfeeding
Breastfeeding often delays the return of ovulation and menstruation due to hormonal influences. Suckling stimulates the pituitary gland to produce high levels of prolactin. This elevated prolactin inhibits gonadotropin-releasing hormone (GnRH) from the hypothalamus. Reduced GnRH then diminishes the pituitary gland’s production of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), essential for ovarian follicle development and ovulation. This process typically prevents the ovaries from releasing an egg, acting as a natural, temporary contraceptive whose effectiveness can vary based on feeding frequency and individual hormonal responses.
Understanding the Lactational Amenorrhea Method
The Lactational Amenorrhea Method (LAM) is a natural family planning approach that relies on breastfeeding to prevent pregnancy. For LAM to be effective, three criteria must be met:
The baby must be less than six months old.
The mother must be exclusively or nearly exclusively breastfeeding, including frequent, on-demand nursing (no more than four hours between daytime feedings and six hours at night).
The mother must not have experienced a menstrual period since childbirth.
When these conditions are met, LAM can be around 98% effective in preventing pregnancy during the first six months postpartum.
When Fertility Can Return
Fertility can return before the first postpartum menstrual period. Ovulation typically precedes the first period, meaning conception is possible without a period as a clear signal. Factors contributing to the return of ovulation and menstruation while breastfeeding include the baby reaching six months, introducing complementary foods or formula, or decreased breastfeeding frequency. Longer intervals between feedings, especially at night, can also lead to a drop in prolactin levels, allowing reproductive hormones to resume activity. The timing of fertility return varies widely.
Signs of Ovulation Without a Period
Observing changes in cervical mucus can help track fertility without a regular menstrual cycle, as it often becomes clear, stretchy, and slippery, resembling raw egg whites, around ovulation. This consistency indicates increased fertility. Ovulation predictor kits (OPKs) detect a surge in luteinizing hormone (LH) 24 to 36 hours before ovulation. Basal body temperature (BBT) tracking can indicate a post-ovulatory temperature shift, but may be less reliable during breastfeeding due to disrupted sleep patterns. Consistent and attentive tracking of these signs is necessary to identify potential ovulation.
Birth Control Options During Breastfeeding
Since LAM is a temporary method and fertility can return unexpectedly, considering other birth control options is a practical step, with progestin-only methods preferred for breastfeeding individuals because they do not typically impact milk supply. These include the progestin-only pill (mini-pill), injections like Depo-Provera, contraceptive implants such as Nexplanon, and hormonal intrauterine devices (IUDs) like Mirena. Combined hormonal methods containing estrogen may reduce milk supply and are often advised against, particularly in the early postpartum period. Non-hormonal options, such as the copper IUD (Paragard), condoms, diaphragms, and spermicides, are also safe and do not affect milk production. Consulting with a healthcare provider is recommended to choose the most suitable birth control method.