How long does it take to get your period after taking oral contraceptive pills?

Although oral contraceptives are very harmful to the body, many people still choose to take them occasionally to prevent unwanted pregnancy. When taking oral contraceptives, you may find that your menstruation is suddenly delayed due to forgetfulness or many other factors. This can be considered as a possibility of unwanted pregnancy. It is also possible that the hormones in the contraceptives may cause delayed menstruation and irregular menstrual cycles. These reasons must be found out.

Will birth control pills delay menstruation?

Contraceptives can delay menstruation, whether it is short-acting oral contraceptives, long-acting oral infertility drugs, or emergency contraceptives, they may delay menstruation. Of course, it does not mean that 100% of them will delay the patient's menstruation. Because when taking short-acting oral contraceptives, as long as there is no missed dose and they are taken in the correct way, the vast majority of women will have normal menstrual cycles and normal menstrual volume. A small number of women may have delayed menstruation if they miss a dose or take it at inconsistent times.

If it is emergency contraceptive pills, the chance of delayed menstruation is relatively high, because emergency contraceptive pills contain progesterone, which is equivalent to the content of short-acting oral contraceptives for eight days. Therefore, emergency contraceptive pills can easily cause endocrine disorders in the body, which can cause delayed or early menstruation.

Main Function

The main functions of contraceptives are: inhibiting ovulation and changing cervical mucus, making it difficult for sperm to penetrate, or reducing the production of glycogen in the uterine glands, making it difficult for the blastocyst to survive, or changing the activity of the uterus and fallopian tubes, hindering the transportation of the fertilized egg.

The mechanism of action is multi-faceted and multi-faceted, and varies depending on the ingredients, preparation, dosage and usage. For example, combined preparations of estrogen and progesterone mainly inhibit ovulation, small doses of progesterone mainly hinder fertilization, and large doses of progesterone mainly prevent implantation. The above classification of application mechanisms is relative.

Steroid hormones

After oral administration, the blood concentration of estrogen and progesterone increases, which inhibits the secretion of gonadotropin-releasing hormone in the hypothalamus through negative feedback. In addition, the sex hormones in the blood also have a direct inhibitory effect on the anterior pituitary, which can reduce the secretion of gonadotropin by the anterior pituitary, and the amount of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in the blood. Since the secretion of FSH is inhibited, the growth and maturation of follicles are hindered, there are no mature follicles for ovulation, and the estrogen peak before ovulation is also cancelled. Because the LH surge during the mid-cycle disappears, the ovulation process is inhibited.

After taking small doses of progesterone orally, it changes the physical and chemical properties of cervical mucus and hinders fertilization. Progesterone can inhibit the secretion of cervical mucus, reducing the amount of mucus but increasing the viscosity and cell content, which is not conducive to sperm penetration, making it difficult for sperm to pass through, thereby hindering fertilization. When progesterone is dominant, sperm capacitation is inhibited and sperm loses its fertilization ability, thus affecting fertilization. Taking small doses of progestin continuously throughout the menstrual cycle can hinder fertilization. Its advantage is that it does not contain estrogen and has fewer side effects, but its contraceptive effect is worse than that of estrogen and progestin combination preparations, and the incidence of irregular bleeding is higher. Rarely used.