Pregnancy

This is not to be seen as a guide that you need to go and follow, but rather a walk through on how pregnancy works. You may feel you know everything there is to know about pregnancy, but read the following information and you may be surprised by the facts.

Who gets pregnant?

In Great Britain, in the year 2000, about 838,000 women became pregnant, resulting in about 658,000 live births.

About 46,000 girls under the age of 18 became pregnant during this time!

Warning! This common myth is not true!

You can't get pregnant if you have sex standing up

How does it all work?

A woman has two ovaries, one on each side of the womb (uterus). These contain her eggs (ova). She is born with all her eggs in place.

A man has two balls (testicles). Sperm are made continuously in great numbers inside each testicle and stored in the epididymis (a small tube at either side of each testicle) for a few weeks until they are fully mature. Sperm are damaged by heat, so the balls are carried outside the body in a soft bag of skin (the scrotum) to keep cool.

What is a woman's menstrual cycle?

The menstrual cycle is from the FIRST DAY OF A PERIOD until the DAY BEFORE THE NEXT PERIOD STARTS. The length of cycle varies - it can be as short as 21 days or as long as 40 days. Whatever the length of cycle, ovulation will happen about 12-16 days before the start of the next period.

Even before birth, a woman has 1-2 million tiny undeveloped eggs in her ovaries - much smaller than this full stop. By puberty the number of eggs has halved. Only around 400 eggs will be released. These eggs all develop - some will be released for fertilisation once a woman reaches puberty and begins her menstrual (monthly) cycle.

  • Each month, the brain sends a chemical message to the ovaries. This causes 12 to 20 eggs to grow in one or other ovary. At the same time the hormone oestrogen begins to thicken the lining of the womb. Usually 1 egg becomes larger than the others and is released into the fallopian tube by the ovary. This is called OVULATION.
  • Ovulation triggers a second hormone, progesterone, to continue to thicken the lining of the womb (endometrium) in preparation for a fertilised egg.
  • The egg lives in the fallopian tube for 12-24 hours. If it's not fertilised and does not implant to start a pregnancy, levels of hormones fall, the womb lining breaks up and a period happens.

What about Sperm?

At puberty, boys start to make sperm in their balls (testes). Each ball (testicle) produces about 2,000 sperm a second, 150 -1000 million a day. They are stored in the testicle for 4 to 6 weeks while they develop ready for ejaculation.

What is Conception?

When a man and women have sexual intercourse the man's penis fits into the woman's vagina. Sperm are released through the penis into the vagina. They swim through the woman's cervix, into the womb, and then into the fallopian tubes. If there is an egg in the tube, hundreds of sperm swim up to reach it.

Fertilisation

  1. One sperm may attach itself to the egg wall and slowly penetrates the wall. It takes about 3 hours for the sperm to enter the egg. Once the sperm is inside, the egg wall hardens to make it impossible for other sperm to get in.
  2. The egg has now been fertilised and moves down the fallopian tube towards the womb.
  3. During the short journey the fertilised egg splits into 2 cells, then into 4, 8, 16 and so on.
  4. About 3-4 days after fertilisation, the egg is now 64 different cells.
  5. About 8 to 10 days after fertilisation, the fertilised egg begins to attach itself to the thick nutritious womb lining. Implantation of the fertilised egg has taken place. It is now called an embryo and the pregnancy has begun.

When is a woman fertile?

To get pregnant, a woman needs to have sex around the time that she ovulates. Her fertile time lasts for 8 - 9 days. It is not always easy to work out when this is - especially if her periods are not regular.

A woman ovulates 12 - 16 days before the start of her next period. Although the released egg will only live for 12-24 hours, sperm can live for up to 7 days. If sperm are already present before ovulation, they may meet the egg when it is released.

What is contraception?

To prevent pregnancy contraception involves using methods that:

  • prevent sperm from meeting the egg
  • Stop an egg being produced

There are 13 different contraception methods:

  • The Combined Pill
  • The progestogen - only pill (POP pill)
  • Male Condom
  • Female Condom
  • Diaphragms and caps
  • Intrauterine device
  • Intrauterine system
  • Contraceptive injections
  • Contraceptive implants
  • Vasectomy
  • Female sterilisation
  • Emergency Contraception

Some of the above contraception methods are quite drastic for a person of your age. Please visit the contraception section of this site to view recommended methods for teens. As a SHOWT user you should already know that condoms protect men and women from both unwanted pregnancy and sexually transmitted infections (S.T.I's) at the same time, do not have to be taken daily, so don't affect your bodies chemistry, and are easy to obtain.

What are the signs of pregnancy?

A woman who thinks she is pregnant, or has missed a period, can get a free pregnancy test at:

  • A young person's clinic
  • Some GPs (ask at reception)
  • Many family planning clinics
  • Some sexual health or Gum clinics

Many women buy a home pregnancy kit, which costs approximately £12 from a pharmacy. Such kits are very reliable.

Signs of early pregnancy vary from person to person, but may include:

  • feeling tired
  • swelling or tenderness of the breasts
  • missing a period
  • A shorter, lighter period than usual
  • Appetite changes (going off certain foods)
  • Nausea or vomiting (often called morning sickness, though its not always in the morning)
  • Feeling bloated or period-like cramps
  • Frequent urination (peeing a lot)
  • Digestion changes
  • Mood changes

If you have missed a period or have any doubts that you may have become pregnant, get yourself checked out as soon as possible!