Contraception



Natural methods


Lactational amenorrhea method

  • There is only a small (about 2%) chance of pregnancy for the first 6 months after delivery if one is: fully breastfeeding or nearly fully breastfeeding (no other liquids given or only water, juice or vitamins given infrequently in addition to breastfeeds; and no long intervals between feeds day or night (i.e. > 4 hours during day and > 6 hours at night)

  • still no menses 56 days (or 7 weeks) after birth

Hence one may not require using any further contraception if the above criteria are met. The failure rate increases if the frequency of breastfeeding decreases (e.g. stopping night feeds, supplementary feeds, use of pacifiers/dummies, when menses return, when > 6 months post-delivery, and if expressing breastmilk rather than feeding off the breast).

Sexual intercourse tends to be difficult during breastfeeding though as the vagina tends to be dry. Use of lubricants like KY Jelly or spermicides may be useful. You may also request to add on a progesterone only pill if you want to have an even lower chance of pregnancy.

Once a period has returned, one should use another contraceptive method if one does not wish to get pregnant.

Fertility awareness

These methods involve one of various methods to reduce the chance of getting pregnant: detection of changes in cervical mucus, symptothermal method (combination of cervical mucus changes and basal body temperature), standard calendar methods.

One would have to be trained properly to use these methods and be motivated to continue using these methods. Otherwise, the failure rate can be high.

For more information, you may want to look at the following websites (Fertility UK or Fertility Awareness Methods).

Withdrawal method (or coitus interruptus)

This requires the male partner to be able to withdraw the penis from the vagina just before ejaculation.

Sometimes, the male partner is not able to withdraw in time.

Even if the male partner is able to withdraw in time, there are still a few sperms present in the fluid before ejaculation. Failure rate is typically high.


Short term reversible methods

Condoms

Nature: Usually rubber condoms. Mechanism of action: It is placed over the penis before penetration to prevent the semen from entering the vagina. Benefits: Prevents sexually transmitted diseases including HIV. Risks:

  • Failure rates range from 2-15 per 100 woman-years, usually due to inconsistent use or incorrect use (e.g. escape of a small amount of semen before or after ejaculation).

  • Rubber allergy

Interactions: There are oils, creams and some medications that one should not use with condoms as these may seriously damage the condoms and lead to rupture of the membranes: baby oil, petroleum jelly, vaseline, and medications like (Canestan, Cyclogest, Dalacin cream, Gyno-Pevaryl, Gyno-Daktarin, Ovestin). It is alright to use water-based lubricants like KY Jelly, and glycerine and silicone lubricants.

Combined oral contraceptive pills

Nature: These contain an estrogen (usually ethinylestradiol) and a progestogen. Mechanism of action: They prevent ovulation primarily, and also has effects on the mucus of the cervix and to prevent implantation. Contraceptive Benefits: 98-99% effective if taken properly, reversible and convenient. Non-contraceptive benefits:

  • Regular periods that are less heavy and less painful, and less premenstrual tension; no pain during ovulation.

  • Less benign conditions like benign breast disease, pelvic inflammatory disease, symptomatic fibroids, acne, endometriosis.

  • Less cancers of the ovary, endometrium (inner lining of the uterus) and colon and rectum. The reduction is by about half to ⅔.

Risks:

  • Possibly a very small increase in risk of venous thromboembolism (e.g. development of blood clots in the calf veins with potential to be dislodged to the lung circulation, and is potentially fatal). The risk is higher during the first year of use, and when restarting use after a break of 4 or more weeks. Patients with a strong family history of venous thromboembolism or with hereditary thrombophilias (e.g. factor V Leiden, protein S and protein C deficiencies) or acquired thrombophilias (e.g. antiphospholipid syndrome) should avoid taking the pills.

  • Possibly increase in risk of heart attacks and strokes. This is especially so if the pill is used in patients who are smokers or who have migraine with aura. Hence smokers, diabetics and those with migraine should avoid taking pills.

  • Increase in tumours:Small increase in breast cancer (odds ratio is 1.24) whilst taking the pill, and reduces to baseline risk 10 years after stopping the pill. Pills should be avoided in those with past history of breast cancer, carriers of known gene mutations e.g. BRCA1. Women with benign breast disease or with a family history of a young first degree relative with breast cancer before age 40 years old may still use the pill though they have a higher background risk than the general population.

  • Small increase in cervical cancer. May speed the transition through the stages of cervical intraepithelial neoplasia (CIN) when there is already HPV infection that has been acquired sexually. Women with CIN may still continue to use the pill if they are being monitored regularly by their doctor.

  • Small increase in risk of very rare benign liver tumours, and also malignant liver tumours. Women with past history of liver tumours should not take the pill.

EVRA combined contraceptive patch

Works like the combined oral contraceptive pills except that the estrogen and progestogen are absorbed through the skin. It is applied on the skin for a week, changed every week for a total of 3 weeks application before having a week off. Occasionally not suitable for patients who develop a rash to the patch.

Long term reversible methods

The popular ones in this group are the intrauterine contraceptive devices that are effective for 5 years. These are usually highly effective contraception and reversible. They are easy to insert in the clinic if one has had a vaginal delivery before. Up to 5 % may drop out especially in the first few menstrual cycles.

Copper IUCD

The main problem of copper IUCD is that the periods for the first 3-6 months tend to be heavier and more painful. Those with heavy and painful periods should avoid having the copper IUCD.

Mirena

It is a good treatment for those with heavy painful periods. Mirena typically makes the periods less painful and less in amount. Some patients have no periods while on Mirena.

A common potential problem of the Mirena is that some patients develop intermittent vaginal bleeding or spotting while on the Mirena which may stop after a few months.

Surgical methods

These methods involve surgery, and are meant to be irreversible. The main problems of these procedures are surgical complications (e.g. bleeding, infection, injury to adjacent organs, anaesthesia) and regret (wish to have a child after the surgical procedure e.g. when having a new relationship, or when one of the children develop a severe medical condition).

Male vasectomy

Can be performed under local anaesthesia, and is generally a safer procedure than female tubal sterilisation (except when the female tubal sterilisation is being done at the time of Caesarean section when the incremental risks of doing the procedure is minimal).

Female tubal sterilisation

It is performed under regional or general anaesthesia, and involves interruption of the Fallopian tubes to prevent the sperms from meeting the eggs. This may be performed by application of clips (e.g. Filshie clips) during laparoscopy, cutting and tying the mid portions of the Fallopian tubes (Pomeroy method) or removal of the fallopian tubes.  Recent studies show that removal of the fallopian tubes has led to a reduction in the risk of ovarian cancer in later years as early cancer of the ovary may start developing from the fallopian tubes.  



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