Page 365 - كتاب تمريض نسا الاكتروني

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Mechanism of action of estrogen as contraceptive*

- Inhibition of ovulation by inhibits production of pituitary gonadotropin.

- Inhibition of egg utilization.

- Acceleration of ovum transport.

Mechanism of action of progestin's as contraceptive*

- Inhibition of ovulation.

- Increase thickness of cervical mucus, which interfere with sperm transport and

decrease sperm ability to penetrate cervical mucus.

- Delay ovum transport.

- Interference with implantation.

1. Progestin only pills (minipill)

- It consists of a small dose of a progestogen as norethisterone.It is taken daily

without interruption. The tablets should be taken at the same time every day

with no more than 3 hours delay as it remains effective for only 27hours.

Mechanism of action:

l - Thick cervical mucus (most important)

2- Atrophic endometrium

3- Inhibit tubal motility & sperm capacitation

4- Suppression of ovulation (50% only)

Advantages

• ASER "available, safe, effective (failure rate 1-2%), reversible"

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