Female Sterilization

The main principle of female sterilization involves cutting or blocking the fallopian tubes so that the egg cannot be reached by the sperm. Over a hundred different ways of doing this have been developed; some are extremely successful, some less so, and some are associated with particular complications. The three main ways of occluding the tubes are: to cut them; to burn them with electrocoagulation; and to block them with clips, ties, bands, plugs or rings. Each of these methods has numerous variations; some of the most common are shown in the diagrams.

Methods

There are several ways of approaching the fallopian tubes to allow the sterilization to be carried out. Female sterilization used to require major abdominal surgery, but the development of new techniques and approaches means that this is no longer the case. The first method is by the mini-laparotomy, or mini-lap. This can be done under a local anaesthetic, or under spinal or general anaesthesia. A small (2-3cm) incision is made in the abdomen; through this the fallopian tube is grasped and occluded in the chosen way. The incision is stitched with absorbable sutures, then the patient rests for about two days. Strenuous activity should be avoided for a week or so.

The second approach is the laparoscopy. This generally is done under a general anaesthetic, but in some cases can be done under a local as an outpatient. A tiny incision (about lcm) is made in the abdomen, then the abdominal cavity is inflated with gas to provide a larger, less cluttered working area. Special instruments are placed in the cavity through the incision; the surgeon can see the organs through the optical part of the instrument, and can manipulate the other parts to occlude the tubes. An ordinary laparotomy (the old method of sterilization) requires a 10cm incision and a much longer hospital stay and recovery period. It also has a higher mortality rate. However this operation is sometimes necessary in place of a laparoscopy or mini-lap, if the woman is ill or has other abdominal complications.

Two approaches have been developed for sterilizing via the vagina. Obviously this means that surgery through the abdominal wall is not required, and the operations have no visible scar. Culpotomy is an ordinary sterilization through the cul-de-sac of the vagina; culdoscopy uses the same approach, but is done with an endoscope (the same type of instrument used in a laparoscopy). A very rarely used method involves approaching the fallopian tubes via the cervix.

One method of sterilization which is not based on occluding the fallopian tubes is hysterectomy, the surgical removal of the uterus. This is a major operation, and is not usually justifiable simply for the purpose of sterilization. This is generally only performed where the uterus itself is diseased, for instance by cancer. Some conditions will be contraindications to abdominal sterilization; these can include cardiorespiratory problems, extreme obesity, previous lower abdominal surgery, a history of pelvic inflammation, or severe endometriosis.

Procedure

The general procedure is the same for most sterilization techniques. You will be asked to bathe or shower, paying especial attention to washing the pubic hair and navel. Some clinics prefer to shave the pubic hair. If the operation is done under a general anaesthetic you will be kept in hospital for a day or two afterwards to check that all has gone well. If it is done under a local, bring a friend or your husband to the clinic to drive you home afterwards, and plan to rest for 48 hours after the operation. Do not do any strenuous activity, sport or lifting for a week or so.

There may be some pain from the incision(s) — aspirin should be able to cope with this. There may also be aching, possibly quite severe, in the shoulders and chest; this is caused by the anaesthetic and the gas used in laparoscopy, but will disappear in 24-48 hours. Occasionally there will be pelvic aching or discomfort.

You will usually be told that you can bathe or shower at any time, but don’t rub your stitches or incisions; pat dry carefully around that area. The clinic will ask you to return for a follow-up check about a month after the operation; it is important to attend. After a sterilization you will be completely protected from conception immediately, provided you did not ovulate in the 48 hours before surgery. If you did, the egg may already be in the lower part of the fallopian tube and available for fertilization, but most clinics will try to arrange the timing of your sterilization so that this is not a danger. You can resume sexual activity as soon as this feels comfortable; stop if you feel any discomfort or pain.

Complications

The mini-lap is generally a very safe operation with a very small percentage of complications (0.5-3% of all operations). Laparoscopy has a similar, or slightly higher, complication rate, although some of these can be related to the general anaesthetic rather than the specific operation. The mortality rate can be 1-10 per 100,000 (compared with up to 8 per 100,000 for mini-lap). Other complications of laparoscopy can include uterine perforation, bleeding, and bowel burns (from electrocoagulation). With both these approaches there is an almost total lack of infection, and they are much better than the vaginal approaches in this respect. Most of the complications can be prevented by careful attention to the surgical procedure.

Culpotomy has a complication rate twice as high as that for abdominal approaches. Ordinary laparotomy has a mortality rate of 10-25 per 100,000, and hysterectomy has a complication and mortality rate 10-100 times greater than that for mini-lap and laparoscopy.

After sterilization there is generally no change in the menstrual pattern. The ovaries are still functioning as normal, and the endometrium is building up and being shed in the same way. One possible, though very rare, complication of sterilization is failure of the operation — in other words, pregnancy! This can occur if the cut ends of the tube rejoin — this is more likely to occur with electrocoagulation than any of the other methods. The failure rate of sterilization is estimated at 0.25% over 4 years. If a woman does become pregnant as a result of sterilization failure, the pregnancy is very likely to be ectopic — some studies say the likelihood may be as high as 50% , compared with 0.5% of pregnancies among other women. Ectopic pregnancy can occur if the fallopian tube is partially blocked — the sperm may be able to get through to fertilize the egg, but the egg, being so much bigger than the sperm, may then not be able to continue down the tube. Ectopic pregnancy is, of course, a life-threatening condition.

Danger signs to be watched for after any sterilization are: fever (over 100.4°F); bleeding from the site of the incision; fainting spells; excessive pain or swelling; symptoms of pregnancy. If any of these occur, see a doctor immediately.

Reversibility

As with vasectomy, the ideal female sterilization operation is one that can be reversed without delay or problems when wished. Also as with vasectomy, this ideal is a long way off, although much research is working in this direction. The success of reversal tends to depend on how much of the fallopian tube is left; at least 3cm of one tube must exist to make the operation worthwhile. Electrocoagulation destroys the most tube, and is the hardest to reverse. Theoretically, plastic clips on the tubes should be the easiest method to reverse, but this is not as simple as it sounds. Tissue tends to grow over the clip, bonding it to the tube, and scar tissue can form in and on the tube itself, leaving it blocked or damaged even when the clip is removed.

Approximately 1% of all sterilization patients request a reversal. Of these, roughly 20% will be selected as suitable candidates; roughly 50% of those selected will have a successful reversal operation. Even when conception occurs, it may take many months, and there is three times the normal chance of failing to deliver a live baby. Once again, sterilization should always be considered permanent. The woman who has the operation in the hope that it can be reversed if she ever changes her mind is likely to be disappointed.

Conclusions

Female sterilization is generally a safe operation with a low rate of complications, although not quite as safe as vasectomy. It is a very effective means of preventing conception, and once the operation has been done there is no need to take any further contraceptive precautions. It used to be the case that sterilization would only be performed if the woman’s age multiplied by the number of children she had was 120 or more (for example if she was twenty-five with five children, or thirty with four). This is no longer the case, and if you are a healthy woman who has decided, with your husband, that you do not intend to bear any more children, sterilization may well be a valid option for you. Sterilization is available on the NHS, but it can be done privately if you prefer or if the NHS waiting list is too long.