Contraception (natural family planning)

Fertility awareness-based methods (FABMs) of family planning have may be offered as alternative methods of family planning (1)

Billings Ovulation Method (BOM), the Creighton Model (CM), and the Symptothermal Method are the more widely used FABMs and can be more narrowly defined as natural family planning

• BOM and CM are based on the examination of cervical secretions to assess fertility
• symptothermal Method combines characteristics of cervical secretions, basal body temperature, and historical cycle data to determine fertility
• FABMs also include the more recently developed Standard Days Method and Two Days Method
• all are distinct from the more traditional rhythm and basal body temperature methods alone
• modern FABMs have typical-use unintended pregnancy rates of 1% to 3% in both industrialized and non-industrialized nations

These methods rely on being able to detect ovulation so as to avoid intercourse at these times. They can be unreliable but enjoy enormous popularity on a worldwide basis where expense and religious or social taboo preclude other forms of contraception. A person's wish to avoid "unnatural" contraception must always be respected.

Reference:

1. World Health Organization. Family planning - a global handbook for providers. 3rd edition. 2018 [internet publication].