The safest, most pleasant, time for travel is between the 12th & 28th week. In early pregnancy many women experience "morning sickness". This can last for many weeks & in a few can cause severe exhaustion & dehydration. A surprisingly high proportion of all pregnancies miscarry in the first few weeks. Heavy or continuous bleeding may be a complication.
If planning a trip when pregnant, one has to think of the worst case scenario. Where would I be if this occurred? Would medical help be safe, clean, of good standard & accessible? After the twelfth week, a pregnancy is better established, the nausea has diminished & the woman's energy levels return to normal.
On the other hand, after 28 weeks the extra weight may cause fatigue & if travelling to a tropical climate the higher tempreatures may not be well tolerated. In the final twelve weeks there is always the possibility of a major complication eg premature labour, toxaemia or haemorrage. For this reason frequent check ups are strongly advised.
Long flights & bus rides increase the risks of venous thrombosis in pregnancy. Sitting in an aisle seat, drinking plenty of water, taking frequent walks & wearing varicose support stockings in-flight help reduce the risk. IATA regulations forbid pregnant women travelling on international flights from 35 weeks onwards.
Here common sense must prevail. High-risk malarial areas are best avoided by pregnant women. Malaria infection in the mother can be devastating to the fetus. The more effective anti-malarial drugs cannot safely be used. There are many alternative destinations which can be enjoyed just as much.
Remote area adventure travel is not a good idea in pregnancy. Medical help may be difficult to access in an emergency. "What about women who live in these places?"… they have no choice & suffer very high rates of reproductive mortality. High altitude trekking & scuba diving are contraindicated in pregnancy. Hot tubs & spas are best avoided because of the risk of raised body temperature & infection.
Generally, all vaccinations are best avoided in the early part of pregnancy. Fever, as a side effect of vaccination, can, in itself, unsettle an early pregnancy. Live vaccines , such as Yellow Fever, should not be given & killed vaccines best left until after the twelfth week of pregnancy or better still, completed prior to the pregnancy. For travel to less developed countries, Hepatitis A protection is essential. This is the commonest vaccine preventible disease of the serious food & water-borne infections & is much more severe if contracted during pregnancy. Illnesses which cause diarrhoea or vomiting can quickly cause dehydration. Strict adherence to the rules of eating & drinking "boil it, cook it, peel it or forget it" is a must. Of great concern is the possibility of taking a medication contraindicated during pregnancy. Presumptive therapeutic regimens for common medical problems should be discussed before travel Taking an appropriately stocked medical kit is sensible.
Whatever the destination overseas, make sure that any unforeseen pregnancy associated medical problem will be covered by your travel health insurance company. Women with previous complicated pregnancies or those expecting a multiple birth may be better advised to stay at home.